1. Technical Field
The present disclosure relates to a wireless local area network (WLAN) technology, and more particularly to a technology for multi-user transmission and reception in the WLAN.
2. Related Art
With the development of information communication technologies, a variety of wireless communication technologies have been developed. Among these technologies, wireless local area network (WLAN) is a technology that Internet access is possible in a wireless way in homes, business or specific service providing areas, using portable terminal such as personal digital assistant (PDA), a laptop computer, a portable multimedia player (PMP), or the like, based on wireless frequency technologies.
WLAN technologies are created and standardized by the IEEE 802.11 Working Group under IEEE 802 Standard Committee. As such WLAN technology becomes more prevalent and its applications become more diverse, there is increasing demand for new WLAN technology that can support a higher throughput than existing WLAN technologies. Very high throughput (VHT) WLAN technology is proposed to support a data rate of 1 Gbps and higher. A WLAN technology according to IEEE 802.11ac standard is a technology providing VHT in sub 6 GHz band, and A WLAN technology according to IEEE 802.11ad standard is a technology providing VHT in 60 GHz band.
In addition to the above-described standards, various standards on WLAN technologies have been developed, and are being developed. As representative recent technologies, a WLAN technology according to IEEE 802.11af standard is a technology which has been developed for WLAN operation in TV white space bands, and a WLAN technology according to IEEE 802.11ah standard is a technology which has been developed for supporting a great number of stations operating with low power in sub 1 GHz band, and a WLAN technology according to IEEE 802.11ai standard is a technology which has been developed for supporting fast initial link setup (FILS) in WLAN systems. Also, IEEE 802.11ax standard is being developed for enhancing frequency efficiency of dense environments in which numerous access points and stations exist.
In the system based on such the WLAN technologies, in a case that data units for multiple users are transmitted through a physical layer convergence procedure (PLCP) protocol data unit (PPDU), methods for informing which users receive the data units and which resources are used for transmitting the data units are needed.